﻿#include <stdio.h>
int main()
{
	int a, s, n, count;
	a = 2, s = 0, n = 1, count = 1;
	while (count <= 7)
	{
		n = n * a;
		s = s + n;
		count++;
	}
	printf("s = % d\n", s);
	return 0;
}